multicast seen as equivalent of caching packets

Alex P. Rudnev alex at
Wed Jun 16 10:28:50 UTC 1999

Sorry; it was my assertion in this tread -:). Through it change nothing...

Why don't start fron the replication/reflection, then go to the 
short-time-caching, may be to the long-time-caching, and then only to the 
multicasting. Those who is playing around multicasting now looks amazing 
- they build a complex, twisted routing schema with the PIM, etc etc to 
deliver usially ONE data stream to the ONE customer -:). May be, to the 
two customers. And then ask _why don't another want to play with them_.

This was the issue - on the first stage, simple packet replication is 
just the same as multicasting, but is much simpler to inplement globally. 
And this is in fact caching with the zero time-to-expire.


> If you think about it briefly, Vadim's assertion that "packet caching"
> and "multicast distribution" are indistinguishable if the packets are
> retained in the cache for essentially 0 time.

> I think Vadim's point is that accepting the validity of the 
> multicasting = caching assertion allows one to consider doing 
> a better job of reducing the consumption of network resources 
> by replayable content than the use of native multicast does.
Just right.

> (This is perhaps why Peter Lothberg and company have been working
> fairly hard at enabling the inflation of the use of Internet multicast,
> since the deployment costs of native IP multicast are so small that
> the ultimate non-scalability of IP multicasting (or multicasting
> in general if you accept Vadim's argument) does not prevent people
> from turning on PIM/SM+mBGP+MSDP.   First you roll (excuse the pun) out
Compare the multicsting listeners and RealVideo or RealAudio or MP3 
listeners; first are 1% of the last. What multicast deploying are you 
talking about, it's a myth yet.

Aleksei Roudnev, Network Operations Center, Relcom, Moscow
(+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095) 230-41-41, N 13729 (pager)
(+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)

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